To move lamps which are mainly intended for clinical use, there are several known devices. In one device, rails and a support movable on these rails are buried in the ceiling; lamps are suspended from this support; and the lamps are movable across an opening provided in the ceiling. In this conventional device, however, the opening is left open without being sealed. As time passes, dust collects in said opening and with an air draft in the room or movement of the lamps, the collected dust falls and spreads, thereby destroying the cleanliness of the room.
Recently, a "clean air" system which assures a sterile, dust-free condition by driving out foul air and introducing fresh, clean air through the ceiling has become increasingly adopted for use mainly in surgical operating rooms.
When the conventional illuminating lamp moving device is used in a room equipped with such a "clean air" system, a turbulence develops around the opening in the ceiling due to the clean air stream and in consequence of this turbulence, the diffusion of dust collected in the opening becomes intense and spoils the sterile condition of the room.
Further this lamp is simply hung on the outside through the opening, and is unsightly.
Also, the conventional device in which, say, the slidable contact for ignition of lamps is easily accessible from the outside involves a hazard of electric shock, which is undesirable from a standpoint of safety.
For these reasons, a lamp-moving device in which the ceiling opening is always sealed, no matter how the lamps are moved and no matter in what position the lamps are located, is necessary.